Exact matrix product state representation and convergence of a fully correlated electronic wavefunction in the infinite basis limit

Gero Friesecke; Benedikt R. Graswald; Örs Legeza

doi:10.1103/physrevb.105.165144

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arXiv · 2112.10210

Exact matrix product state representation and convergence of a fully correlated electronic wavefunction in the infinite basis limit

Gero Friesecke·Benedikt R. Graswald·Örs Legeza

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Abstract

In this article we present the exact representation of a fully correlated electronic wavefunction as the single-particle basis approaches completeness. It consists of a half-infinite chain of matrices of exponentially increasing size. The complete basis limit is illustrated numerically using the density matrix renormalization group method by computing the core-valence entanglement in the C$_2$ ground state in increasing subsets of cc-pVTZ and pVQZ bases until convergence is reached.

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Gero Friesecke, Benedikt R. Graswald, Örs Legeza. 2021-12-19. Exact matrix product state representation and convergence of a fully correlated electronic wavefunction in the infinite basis limit. https://doi.org/10.1103/physrevb.105.165144

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